ndb - bug#19201 (4.1), see comment in NdbBlob.cpp

ndb/test/ndbapi/testBlobs.cpp:
  option -fac (fetch across commit)
ndb/tools/delete_all.cpp:
  option --transactional (default remains truncate)
mysql-test/r/ndb_blob.result:
  bug#19201
mysql-test/t/ndb_blob.test:
  bug#19201
ndb/include/kernel/signaldata/TcKeyReq.hpp:
  bug#19201
ndb/include/ndbapi/NdbBlob.hpp:
  bug#19201
ndb/src/ndbapi/NdbBlob.cpp:
  bug#19201

mysql-test/r/ndb_blob.result

@@ -481,14 +481,22 @@ msg text NOT NULL
 insert into t1 (msg) values(
 'Tries to validate (8 byte length + inline bytes) as UTF8 :(
 Fast fix: removed validation for Text.  It is not yet indexable
-so bad data will not crash kernel.
-Proper fix: Set inline bytes to multiple of mbmaxlen and
-validate it (after the 8 byte length).');
+so bad data will not crash kernel.');
 select * from t1;
 id	msg
 1	Tries to validate (8 byte length + inline bytes) as UTF8 :(
 Fast fix: removed validation for Text.  It is not yet indexable
 so bad data will not crash kernel.
-Proper fix: Set inline bytes to multiple of mbmaxlen and
-validate it (after the 8 byte length).
+drop table t1;
+create table t1 (
+a int primary key not null auto_increment,
+b text
+) engine=ndbcluster;
+select count(*) from t1;
+count(*)
+500
+truncate t1;
+select count(*) from t1;
+count(*)
+0
 drop table t1;

mysql-test/t/ndb_blob.test

@@ -403,10 +403,29 @@ create table t1 (
 insert into t1 (msg) values(
 'Tries to validate (8 byte length + inline bytes) as UTF8 :(
 Fast fix: removed validation for Text.  It is not yet indexable
-so bad data will not crash kernel.
-Proper fix: Set inline bytes to multiple of mbmaxlen and
-validate it (after the 8 byte length).');
+so bad data will not crash kernel.');
 select * from t1;
 drop table t1;
 
+# -- bug #19201
+create table t1 (
+  a int primary key not null auto_increment,
+  b text
+) engine=ndbcluster;
+--disable_query_log
+set autocommit=1;
+# more rows than batch size (64)
+# for this bug no blob parts would be necessary
+let $1 = 500;
+while ($1)
+{
+  insert into t1 (b) values (repeat('x',4000));
+  dec $1;
+}
+--enable_query_log
+select count(*) from t1;
+truncate t1;
+select count(*) from t1;
+drop table t1;
+
 # End of 4.1 tests

ndb/include/kernel/signaldata/TcKeyReq.hpp

@@ -39,6 +39,7 @@ class TcKeyReq {
   friend class NdbOperation; 
   friend class NdbIndexOperation;
   friend class NdbScanOperation;
+  friend class NdbBlob;
   friend class DbUtil;
 
   /**

ndb/include/ndbapi/NdbBlob.hpp

@@ -275,6 +275,7 @@ private:
   bool isWriteOp();
   bool isDeleteOp();
   bool isScanOp();
+  bool isTakeOverOp();
   // computations
   Uint32 getPartNumber(Uint64 pos);
   Uint32 getPartCount();

ndb/src/ndbapi/NdbBlob.cpp

@@ -23,6 +23,7 @@
 #include <NdbBlob.hpp>
 #include "NdbBlobImpl.hpp"
 #include <NdbScanOperation.hpp>
+#include <signaldata/TcKeyReq.hpp>
 
 #ifdef NDB_BLOB_DEBUG
 #define DBG(x) \
@@ -290,6 +291,13 @@ NdbBlob::isScanOp()
     theNdbOp->theOperationType == NdbOperation::OpenRangeScanRequest;
 }
 
+inline bool
+NdbBlob::isTakeOverOp()
+{
+  return
+    TcKeyReq::getTakeOverScanFlag(theNdbOp->theScanInfo);
+}
+
 // computations (inline)
 
 inline Uint32
@@ -1218,8 +1226,22 @@ NdbBlob::preExecute(ExecType anExecType, bool& batch)
     if (isUpdateOp() || isWriteOp() || isDeleteOp()) {
       // add operation before this one to read head+inline
       NdbOperation* tOp = theNdbCon->getNdbOperation(theTable, theNdbOp);
+      /*
+       * If main op is from take over scan lock, the added read is done
+       * as committed read:
+       *
+       * In normal transactional case, the row is locked by us and
+       * committed read returns same as normal read.
+       *
+       * In current TRUNCATE TABLE, the deleting trans is committed in
+       * batches and then restarted with new trans id.  A normal read
+       * would hang on the scan delete lock and then fail.
+       */
+      NdbOperation::LockMode lockMode =
+        ! isTakeOverOp() ?
+          NdbOperation::LM_Read : NdbOperation::LM_CommittedRead;
       if (tOp == NULL ||
-          tOp->readTuple() == -1 ||
+          tOp->readTuple(lockMode) == -1 ||
           setTableKeyValue(tOp) == -1 ||
           getHeadInlineValue(tOp) == -1) {
         setErrorCode(tOp);

ndb/test/ndbapi/testBlobs.cpp

@@ -45,6 +45,7 @@ struct Opt {
   bool m_dbg;
   bool m_dbgall;
   const char* m_dbug;
+  bool m_fac;
   bool m_full;
   unsigned m_loop;
   unsigned m_parts;
@@ -73,6 +74,7 @@ struct Opt {
     m_dbg(false),
     m_dbgall(false),
     m_dbug(0),
+    m_fac(false),
     m_full(false),
     m_loop(1),
     m_parts(10),
@@ -111,6 +113,7 @@ printusage()
     << "  -dbg        print debug" << endl
     << "  -dbgall     print also NDB API debug (if compiled in)" << endl
     << "  -dbug opt   dbug options" << endl
+    << "  -fac        fetch across commit in scan delete [" << d.m_fac << "]" << endl
     << "  -full       read/write only full blob values" << endl
     << "  -loop N     loop N times 0=forever [" << d.m_loop << "]" << endl
     << "  -parts N    max parts in blob value [" << d.m_parts << "]" << endl
@@ -1260,23 +1263,11 @@ deleteScan(bool idx)
       CHK((ret = rs->nextResult(false)) == 0 || ret == 1 || ret == 2);
       if (++n == g_opt.m_batch || ret == 2) {
         DBG("execute batch: n=" << n << " ret=" << ret);
-        switch (0) {
-        case 0: // works normally
+        if (! g_opt.m_fac) {
           CHK(g_con->execute(NoCommit) == 0);
-          CHK(true || g_con->restart() == 0);
-          break;
-        case 1: // nonsense - g_con is invalid for 2nd batch
-          CHK(g_con->execute(Commit) == 0);
-          CHK(true || g_con->restart() == 0);
-          break;
-        case 2: // DBTC sendSignalErrorRefuseLab
-          CHK(g_con->execute(NoCommit) == 0);
-          CHK(g_con->restart() == 0);
-          break;
-        case 3: // 266 time-out
+        } else {
           CHK(g_con->execute(Commit) == 0);
           CHK(g_con->restart() == 0);
-          break;
         }
         n = 0;
       }
@@ -1824,6 +1815,10 @@ NDB_COMMAND(testOdbcDriver, "testBlobs", "testBlobs", "testBlobs", 65535)
 	continue;
       }
     }
+    if (strcmp(arg, "-fac") == 0) {
+      g_opt.m_fac = true;
+      continue;
+    }
     if (strcmp(arg, "-full") == 0) {
       g_opt.m_full = true;
       continue;

ndb/tools/delete_all.cpp

@@ -23,17 +23,21 @@
 #include <NDBT.hpp>
 
 static int clear_table(Ndb* pNdb, const NdbDictionary::Table* pTab,
-                       bool commit_across_open_cursor, int parallelism=240);
+                       bool fetch_across_commit, int parallelism=240);
 
 NDB_STD_OPTS_VARS;
 
 static const char* _dbname = "TEST_DB";
+static my_bool _transactional = false;
 static struct my_option my_long_options[] =
 {
   NDB_STD_OPTS("ndb_desc"),
   { "database", 'd', "Name of database table is in",
     (gptr*) &_dbname, (gptr*) &_dbname, 0,
     GET_STR, REQUIRED_ARG, 0, 0, 0, 0, 0, 0 },
+  { "transactional", 't', "Single transaction (may run out of operations)",
+    (gptr*) &_transactional, (gptr*) &_transactional, 0,
+    GET_BOOL, NO_ARG, 0, 0, 0, 0, 0, 0 },
   { 0, 0, 0, 0, 0, 0, GET_NO_ARG, NO_ARG, 0, 0, 0, 0, 0, 0}
 };
 static void usage()
@@ -82,18 +86,11 @@ int main(int argc, char** argv){
       ndbout << " Table " << argv[i] << " does not exist!" << endl;
       return NDBT_ProgramExit(NDBT_WRONGARGS);
     }
-    // Check if we have any blobs
-    bool commit_across_open_cursor = true;
-    for (int j = 0; j < pTab->getNoOfColumns(); j++) {
-      NdbDictionary::Column::Type t = pTab->getColumn(j)->getType();
-      if (t == NdbDictionary::Column::Blob ||
-          t == NdbDictionary::Column::Text) {
-        commit_across_open_cursor = false;
-        break;
-      }
-    }
-    ndbout << "Deleting all from " << argv[i] << "...";
-    if(clear_table(&MyNdb, pTab, commit_across_open_cursor) == NDBT_FAILED){
+    ndbout << "Deleting all from " << argv[i];
+    if (! _transactional)
+      ndbout << " (non-transactional)";
+    ndbout << " ...";
+    if(clear_table(&MyNdb, pTab, ! _transactional) == NDBT_FAILED){
       res = NDBT_FAILED;
       ndbout << "FAILED" << endl;
     }
@@ -103,7 +100,7 @@ int main(int argc, char** argv){
 
 
 int clear_table(Ndb* pNdb, const NdbDictionary::Table* pTab,
-                bool commit_across_open_cursor, int parallelism)
+                bool fetch_across_commit, int parallelism)
 {
   // Scan all records exclusive and delete 
   // them one by one
@@ -134,7 +131,7 @@ int clear_table(Ndb* pNdb, const NdbDictionary::Table* pTab,
       }
       goto failed;
     }
-    
+
     pOp = pTrans->getNdbScanOperation(pTab->getName());	
     if (pOp == NULL) {
       goto failed;
@@ -165,7 +162,7 @@ int clear_table(Ndb* pNdb, const NdbDictionary::Table* pTab,
       } while((check = rs->nextResult(false)) == 0);
       
       if(check != -1){
-        if (commit_across_open_cursor) {
+        if (fetch_across_commit) {
           check = pTrans->execute(Commit);   
           pTrans->restart(); // new tx id
         } else {
@@ -196,7 +193,7 @@ int clear_table(Ndb* pNdb, const NdbDictionary::Table* pTab,
       }
       goto failed;
     }
-    if (! commit_across_open_cursor && pTrans->execute(Commit) != 0) {
+    if (! fetch_across_commit && pTrans->execute(Commit) != 0) {
       err = pTrans->getNdbError();
       goto failed;
     }